Changes of the immune system in the pathogenesis of primary Sjögren's syndrome

There are many studies done to determine factors what can cause susceptibility to Sjögren's syndrome. Despite intensive research of the immune system, the model of the Sjögren's syndrome pathogenesis is not completely clear. Lymphopenia is a common symptom found in the pSS patients. Numerous studies are performed in order to determine the causes of lymphopenia, but there is a lack of detailed studies to reveal which cell population counts increase or decrease. Scarce studies are done to associate the changes in the immune cell population and the expression of humoral factors in the peripheral blood of pSS patients. The aim of dissertation work was to investigate the changes of the components of the systemic immune response in the peripheral blood of patients with primary Sjögren's syndrome (pSS) with different manifestations of the disease. In this study, a comprehensive analysis of B, NK and T cell populations and humoral factors in the peripheral blood of pSS patients was performed. For the first time the expression of CD57 and CD27 markers on CD8+ T cell population was analyzed. For the first time Th17/Th1-like cells in the peripheral blood of pSS patients were identified and imbalance in the distribution of T helper cell population was revealed. It can be explained by the significant increase of Th17/Th1-like lymphocyte population. The levels of IL-27 and IL-35 in sera of pSS patients were measured (not in the model system) for the first time as well. Primary Sjögren’s syndrome patients with extra-glandular manifestations have higher imbalance of B cell homeostasis, than patients with only glandular manifestations. This is caused by an imbalance in the expression of BAFF, IgG, κ and λ FLC and C4d in serum